Since an organic EL display panel can be manufactured at a relatively low cost and moreover the size of the EL display panel itself can be easily increased, it is recently considered promising to use the panel to products such as a digital clock, a phone, a laptop computer, a pager, a mobile phone, a calculator, and the like. In general, an organic EL device constituting an organic EL display panel is composed of a transparent electrode as an anode, an organic functional layer, and a metal electrode as a cathode which are sequentially layered on a surface of a transparent substrate. Light can be emitted from the substrate side in such a manner that the exciters, which are formed when electrons and holes injected from both the electrodes in the state that the organic functional layer is sandwiched between the anode and the cathode are recombined, return from an excited state to a ground state and generate light.
In this case, the organic functional layer is, for example, a single layer of a light emission layer, a three-layered structure of an organic hole transport layer, a light emission layer, and an organic electron transport layer, or a two-layered structure of an organic hole transport layer and a light emission layer, and further a layered body provided with an electron or hole injection layer and a carrier block layer interposed between appropriate layers in the above structures.
Incidentally, the organic EL device has a problem in that when it is exposed to the atmosphere, it is liable to be deteriorated because it is affected by moisture, gases such as oxygen and the like, and a certain kind of other molecules existing in an environment in which it is used. In particular, the organic EL device is disadvantageous in that the characteristics thereof are prominently deteriorated in the interface between the electrodes and the organic functional layer thereof and thus light emission characteristics such as luminance and color, and the like are deteriorated.
To solve the above problems, it is known that after an organic EL device, which has first and second display electrodes and at least one organic functional layer sandwiched between the respective display electrodes and composed of an organic compound, is disposed on a surface of a substrate such as a glass and the like, a high-molecular compound film, which covers the organic EL device and the surface of the substrate in the periphery of the organic EL device, and an inorganic barrier film, which covers the high-molecular compound film and the edge thereof as well as covers the surface of the substrate in the periphery of the high-molecular compound film are sequentially layered. In this case, an aromatic polyurea film composed of a material monomer formed by an evaporation-polymerization method is used as the high-molecular compound film, and a silicon nitride film or a silicon nitride-oxide film is used as the inorganic barrier film (Patent Document 1).    Patent Document 1: Japanese Patent Application Laid-Open Publication No. 2004-281247 (refer to, for example, the description of paragraphs 0012, 0013)